The 2023 Women's South Island League, is the 2nd season of the 2nd level women's football in New Zealand and the 1st season under the name Women's South Island League.
Coastal Spirit SAS are the South Island Qualifying League, known as Mainland Women's Premiership, champions and the 2022 Women's South Island Championship champions and Dunedin City Royals are the FS Women's Premiership champions, Women's South Island League Playoff winners and 2022 Women's South Island Championship runners up.
The South Island League is the culmination of two regional federations, each of which provide teams to the Women's South Island League. The top four teams in the Women's Premier League and top two teams from the Women's Southern Premiership qualify for entry into the South Island League.
The season started on 1 April, and finished on 28 May, being a single round. The league determined the top four teams in Mainland's federation, who went on to play the top two teams from Southern Football. The bottom three teams played in the Canterbury Women's Premiership, starting after this league finished, and were joined by the top three teams of Canterbury Women's Championship Division 1.
The four teams from the 2022 league - Cashmere Technical, Coastal Spirit SAS, FC Nomads United and University of Canterbury - were joined by Halswell Christchurch United, Nelson Suburbs, and Selwyn United. Halswell Christchurch United were a combined team of Halswell United and Christchurch United; similarly FC Nomads United was a combined team from Nomads United and FC Twenty 11.
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All seven teams from the previous season competed.
The league was a single round, with the top four teams advancing to the South Island League southern playoffs. The bottom three teams played in the ODT Women's Southern Championship, with the two teams who did not qualify for the South Island League.
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Each team played each other once over three rounds, with the top two advancing to the South Island League, while the bottom two played in the ODT Women's Southern Championship.
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The six teams each played every other team twice, once at home and once away.
Cashmere Technical, Coastal Spirit SAS and Dunedin City Royals returned to the league, joined by Otago University from Southern Football, with Nelson Suburbs and University of Canterbury from Mainland Football.
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